Google Glass can, in theory, be used for lots of things, but sexually explicit material is one area now off limits to developers.

"We don't allow Glassware content that contains nudity, graphic sex acts or sexually explicit material," according to Google's Glass platform developer policies, which were updated Saturday to offer more information about what developers can and cannot do with the software they make for Glass, which Google refers to as "Glassware."

Google's clarified stance comes just as a Glass pornography app, called "Tits and Glass," made by four developers at MiKandi, a mobile app store for adult content, launched Monday. Prior to Monday, Google's glass developer policies did not specifically address sexual content.

The app, which purports to be the first adult software for Glass, lets users "share racy content from their devices directly to other Glass users and online" at the app website, its developers said. The software also comes preloaded with "premium adult photos," with more adult content recorded using Google Glass on the way, Seattle-based MiKandi said in an announcement.

MiKandi only became aware of the new developer policies after its app was launched. As of press time, they had not been directly contacted by Google. As for whether the updated policies may change the company's plans, "we're discussing that right now," said MiKandi co-founder and Glass porn developer Jesse Adams.

Google Glass is worn like regular glasses. The device, which currently is in the hands of several thousand people who paid US$1,500 to be among its first testers, includes a small, square display that hangs in front of the wearer's right eye, next to a tiny camera.

The device has not been released to the general public, but critics have raised questions about privacy, such as the extent to which Glass is capable of gathering personal information about people nearby.

The company so far has largely stood back to let developers shape the direction of Glass applications. But some of the controversy surrounding Glass, including the recently updated developer policies, shows that, in some areas at least, Google will step in to draw more lines in the developer sandbox.

"Google must be afraid of how powerful their own Glasses are," MiKandi's Adams said.

Even without developers steering Glass into risque territory, the product is already feared by some as a tool for stalkers, perverts and pedophiles.

Several weeks ago, members of a U.S. congressional group on privacy wrote to Google CEO Larry Page requesting information about a host of issues, such as whether the company is considering revising its privacy policy to account for the sensory functions present in Glass.

Violations of its developer policies are violations of Glass' API terms of service, Google says, "and can result in the disablement or removal of your application, being prohibited from providing future applications, or termination of your Google account."

Still, MiKandi hopes to stay in the adult content space on Glass. "We're not going to just stop," Adams said. "We have to think about our next strategy."